A cellular network is a radio network distributed over land areas referred to as cells. Each cell can be served by at least one fixed-location transceiver referred to as a cell site or base station. When joined together, the cells provide radio coverage over a wide geographic area, such as a city or larger area. This enables a large number of portable transceivers (e.g., mobile telephones, pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations. The portable transceivers may also communicate when the transceivers are moving through more than one cell during transmission.
Another shorter range wireless communication technology is defined under the Wireless Fidelity (WiFi) standard. WiFi is a branded standard for wirelessly connecting electronic devices. A WiFi device, such as a personal computer, video game console, smartphone, or digital audio player can connect to the Internet via a WiFi network access point. A WiFi access point (or hotspot) has a range of about 20 meters (or about 65 feet) indoors and possibly a greater range outdoors. Multiple overlapping access points can cover large areas. The WiFi Alliance identifies a range of connectivity technologies for WiFi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards, including wireless local area network (WLAN) connections, device to device connectivity (such as WiFi Peer to Peer or WiFi Direct), Personal area network (PAN), local area network (LAN), and even some limited wide area network (WAN) connections. Some portable devices, such as some smartphones and tablet personal computers (PCs), comprise transceivers (radios) for both cellular and WiFi communications, e.g., to provide both voice and data services.